Wheel axle assembly

ABSTRACT

A wheel assembly quick release lever pivots against a thrust washer to apply a force along the length of an axle. The thrust washer is pressed toward a sleeve nut at the opposite end of the axle, which displaces the thrust washer relative to the axle, drawing the sleeve nut and a pair of compression rings toward one another deeper into conical cavities of dropouts. The radially outwardly facing surfaces of the compression rings firmly seat against the tapered cavities of the closed bore dropouts, and the radially inwardly facing surfaces of the compression rings firmly seat against the axle to provide resistance to rotational movement of the axle relative to the dropouts. The inboard surfaces of the dropouts seat against the load-bearing axle faces of the hub, which provides resistance to lateral movement.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.13/072,118 filed Mar. 25, 2011, now issued as U.S. Pat. No. 8,820,853,which claims the benefit of U.S. Provisional Application No. 61/317,301filed Mar. 25, 2010, all of which are hereby incorporated by reference.

STATEMENT REGARDING FEDERALLY-SPONSORED RESEARCH AND DEVELOPMENT

(Not Applicable)

REFERENCE TO AN APPENDIX

(Not Applicable)

BACKGROUND OF THE INVENTION

The present invention relates to axle assemblies for mounting wheels tovehicles. More particularly, the invention relates to conveniently andsecurely mounting wheels to bicycles in a manner that allows removal ofthe wheel without tools.

It has long been known that the quick and easy removal of wheels frombicycles, without the need for tools, has advantages for timely repairof tires and other wheel components and for convenient transport andstorage of the entire bicycle. At the same time, a secure and rigidconnection of the bicycle wheel is necessary for good handlingcharacteristics and rider safety. A secure connection is most importantin the case of the front wheel, since unwanted detachment or instabilityof the front wheel disproportionately exposes the rider to the risk of aserious accident.

Axle designs that fix a wheel to a bicycle without the need for toolshave been popular for many years. In one conventional design, the endsof the wheel axle are displaced perpendicular to the axle's length intoslots or “dropouts” in the front fork blades or rear stays of thebicycle. Then the axle is clamped against the faces of the slots in theaxial direction by the pressure of a lever-operated cam or screw. Raisedtabs or ridges on the faces of the fork blades help to retain the wheelin the slot even if the lever or screw loosens unintentionally. Indesign variations, other mechanically engaging features are added to thebasic design to prevent unintended wheel detachment, ensure a consistentlevel of clamping force and improve convenience of wheel mounting anddismounting.

Axle systems that secure the axle in slots with clamping force typicallyprovide less stability of the wheel than wheel systems that secure theaxle ends in substantially closed bores. Especially where stresses onthe bicycle wheel are high, such as in off-road cycling, theadvantageous stability of closed bore dropouts have favored “thru-axle”designs. In these designs, a mounting axle is inserted through the forkends and wheel hub from one side of the bicycle along the axle's length.The axle engages a closed bore in at least one of the fork legs. In moretraditional versions of the system, clamps on the ends of the fork legstightly connect the mounting axle to the fork on either side while anend bolt secures the mounting axle somewhat in the axial direction.Typically, however, such designs do not clamp the fork legs tightlyagainst the hub in the axial direction. Moreover, the dropout bores havenarrow slots in order to clamp around the axle by means of screw or camfasteners. The narrow slots of the dropout bores result in less rigidityunder high lateral loads on the wheel than fully closed bores.

The inconvenience of securing multiple clamps has led to the design of“quick release” versions of the thru-axle arrangement. Examples of quickrelease versions include the devices of U.S. Pat. No. 7,090,308, UnitedStates Patent Application Publication Numbers 2009/0072613 and2009/0140571 and British Patent No. GB2414971B. These devices offerenhanced wheel retention compared to axles that engage open slots.However, with the exception of the first device cited, all these devicesstabilize the wheel simply by using the mounting axle to clamp the forklegs against the ends of the hollow axle of the hub.

Regarding the devices cited above, the mounting axles fit tightly in thebore or bores of the fork legs and engage the outboard surfaces of thelegs to apply tension in the axial direction to pull the legs inwardlyagainst the hub. However, these devices have no torsionally rigidconnection to the legs, which allows torsional flexure to go withoutresistance. Torsional flexure occurs when a lateral force is applied tothe wheel tending to rotate the wheel to the side relative to thehandlebars. In this situation, one fork leg tends to move forwardlyrelative to the other fork leg about the portion of the fork thatconnects the two fork legs. This pivoting causes the walls defining eachleg's apertures (through which the axle extends) to rotate relative tothe axle in opposite directions.

This phenomenon is demonstrated by imagining a conventional bicyclewheel secured in a fork with one of the above-referenced devices, andthe structures connecting the two fork legs being cut. In a conventionaldesign, the two legs could rotate around the wheel axis independently ofone another with relatively little resistance. Although cutting of thestructure connecting the forks would rarely be encountered, it is commonto encounter torsional forces of the forks against the axle as describedabove. Therefore, resistance to torque provides advantages.

The quick release thru-axle device disclosed in U.S. Pat. No. 7,090,308clamps the mounting axle to the fork leg bores when a cam lever isoperated by expanding the slotted ends of the hollow mounting axle.Consequently, it provides significant resistance against independentrotational flexure of the legs. Nevertheless, unlike the other devicescited in the previous paragraph, it does not clamp the hub tightlyagainst the fork dropouts in the axial direction.

The need therefore exists for an improved wheel axle system for abicycle or other vehicle.

BRIEF SUMMARY OF THE INVENTION

The invention is a clamping assembly used where an axle assembly isfixed to first and second structural members, such as bicycle fork legs.The axle assembly has first and second ends and a longitudinal axis. Thefirst axle assembly end is releasably fixed to the first structuralmember and the second end is releasably fixed to the second structuralmember.

The axle assembly rotatably mounts a wheel and hub assembly on an axleportion of the axle assembly, which axle portion is located between thefirst and second axle assembly ends. The first structural member has asubstantially closed bore dropout with a first side, from which the axleportion extends, and a second side. The second structural member has asubstantially closed bore dropout.

The improvement to the clamping assembly includes a first compressionmember, which can be a slotted ring, disposed in a first tapered cavityin the first structural member's dropout. The axle portion extendsthrough an aperture in the first compression member and the firstcompression member and the first tapered cavity are axially aligned withthe axle portion.

A second compression member is disposed in a second tapered cavity inthe second structural member's dropout. The axle portion extends throughan aperture in the second compression member and the second compressionmember and the second tapered cavity are axially aligned with the axleportion.

An abutment member, which can be a washer, is adjacent to a largediameter end of the first compression member and axially displaceablerelative to the axle portion. A quick release is disposed at the firstend for providing a force acting in the direction of the longitudinalaxis between the first and second ends of the axle assembly. The forceclamps the axle assembly to the structural members, whereby the axleassembly can be removed from the substantially closed bore dropout in adirection parallel to the longitudinal axis.

In a preferred embodiment of the invention, each of the structuralmembers includes a fully closed bore dropout. A threaded connectionpreferably releasably fixes at least one of the axle assembly ends to acorresponding one of the structural members. The quick releasepreferably includes a cam configured to apply a clamping force in thedirection of the longitudinal axis. The first and second compressionmembers preferably comprise tapered and slotted compression rings.

Such a system has connections that resist independent rotationalmovement of the fork legs or similar wheel-supporting structures. Theinvention also accomplishes clamping of the hub in the axial directionagainst fully closed bore dropouts on either side for maximum lateralrigidity of the wheel mounting. Such a system provides convenience ofoperation that allows quick installation and removal of the wheelwithout tools, including the ability to set the clocked position of thecam lever, when closed, wherever the end user desires.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 is a schematic view in perspective illustrating a front wheelassembly of a bicycle in which the front wheel is mounted to a frontfork using the present invention.

FIG. 2 is an exploded view in perspective illustrating the presentinvention.

FIG. 3 is an end view in section illustrating a hub and axle accordingto the present invention.

FIG. 4 is an exploded view in perspective illustrating an alternativeembodiment of the present invention.

FIG. 5 is an exploded view in perspective illustrating anotheralternative embodiment of the present invention.

In describing the preferred embodiment of the invention which isillustrated in the drawings, specific terminology will be resorted tofor the sake of clarity. However, it is not intended that the inventionbe limited to the specific term so selected and it is to be understoodthat each specific term includes all technical equivalents which operatein a similar manner to accomplish a similar purpose. For example, theword connected or terms similar thereto are often used. They are notlimited to direct connection, but include connection through otherelements where such connection is recognized as being equivalent bythose skilled in the art.

DETAILED DESCRIPTION OF THE INVENTION

U.S. Provisional Application Ser. No. 61/317,301 filed Mar. 25, 2010,which is the above claimed priority application, is incorporated in thisapplication by reference.

FIG. 1 shows a front wheel assembly 100 of a bicycle, which has a frontwheel 140 mounted to a front fork 1. The fork 1 has a pair of fork legs30 and 40 on opposite sides of the wheel 140. As illustrated in FIGS. 1,2 and 3, closed bore dropouts 102 and 104 are formed at the lower endsof the fork legs 30 and 40, and the axle assembly 50 extends through thedropouts 102 and 104 and the hub 12 to fix the wheel 140 to the fork 1.

The dropouts 102 and 104 have tapered, more specifically conical,cavities 112 and 114 extending therethrough as best viewed in FIG. 3.The cavities 112 and 114 are aligned along a line that defines the axisof rotation of the hub 12. The axle assembly 50 extends through thedropouts 102 and 104 and attaches to the fork legs 30 and 40. The hub 12is then rotatably mounted to the axle assembly 50 as explained in moredetail below after the axle assembly is described.

A quick release lever 7 with a cam 72 is mounted at one end of the axleassembly 50. The lever 7 pivotably attaches to the linking rod 6 by thepin 8 a. The pin 8 b attaches the linking rod 6 to the mounting axleportion 2. The linking rod 6 extends through an abutment member, such asthe thrust washer 9, a compression ring, such as the tapered, slit ring3, and the return spring 13 as shown in FIG. 3. A compression ring, suchas the tapered, slit ring 4, is disposed in the conical cavity 114 ofthe closed bore dropout 104 on the side of the fork leg 40 opposite thequick release lever 7.

The sleeve nut 5 is knurled on its radially outwardly facing surface, sothat it can easily be rotated by hand, and is preferably threaded on itsradially inwardly facing surface so it can receive the radiallyoutwardly facing threads 22 on the end of the axle portion 2. Of course,other fastening structures can be used. One end of the sleeve nut 5abuts a large, outboard end of the tapered compression ring 4. Theopposite end of the portion of the sleeve nut 5 that is flared outwardlyto form a flange seats against the wire clip 10, which thereby capturesand retains the sleeve nut 5 within the closed bore dropout 104. Thewire clip 10 is a spring metal member that has an open circular shapethat is retained in the groove 116 formed in the sidewall of the cavity114 so that the wire clip 10 cannot move along the length of the axle 2and protrudes slightly into the barrel of the cavity 114. Thus, thesleeve nut 5 cannot move outboard from its position shown in FIG. 3 dueto the wire clip 10, and the sleeve nut 5 cannot move inboard more thana short distance because it abuts the large diameter end of thecompression ring 4, which in turn is captured on the inboard side by thetaper of the sidewall defining the cavity 114. Thus, the sleeve nut 5 isrotatably mounted to the dropout 104, but is permanently retained withinthe dropout cavity 114.

The threads 22 on the end of the mounting axle portion 2 of the axleassembly 50 are shown in FIG. 3 engaged with the sleeve nut 5. When thecam 72 of the quick release lever is forced against the thrust washer 9by the lever 7 being pivoted, an inboard-directed, longitudinal force isapplied along the length of the axle portion 2 as the larger radiusportion of the cam 72 slides against the thrust washer 9. By thislongitudinal force, the thrust washer 9 is pressed toward the sleeve nut5, thereby displacing the thrust washer 9 relative to the axle portion2. This movement draws the sleeve nut 5, and therefore the compressionring 4, toward the compression ring 3, thus causing both compressionrings 3 and 4 to slide toward one another in their respective taperedcavities 112 and 114. This continues as long as the lever 7 is pivotedor until the force necessary to further insert the compression rings 3and 4 into the tapered cavities is too great for the person pivoting thelever 7 to generate. Of course, it is possible to omit the thrust washer9 and seat the cam surface directly against the compression ring 3.

Because the clamping force is directed against the large ends of thecompression rings 3 and 4, the rings are thereby driven into the conicalcavities 112 and 114 of the closed bore dropouts 102 and 104,respectively. Therefore, by the movement of the lever 7, the radiallyoutwardly facing surfaces of the compression rings 3 and 4 are firmlyseated against the tapered cavities 112 and 114 of the closed boredropouts, and the radially inwardly facing surfaces of the compressionrings 3 and 4 are firmly seated against the axle portion 2. Thisprovides enormous frictional resistance to rotational movement of theaxle portion 2 relative to the dropouts 102 and 104. Furthermore, theinboard surfaces of the dropouts seat against the load-bearing axlefaces of the hub 12, which provides substantial resistance to lateralmovement.

The preferably aluminum compression rings 3 and 4 have longitudinalslots 32 and 42, respectively, which allow the rings to compresstransversely (radially) when they are driven into the conical cavities112 and 114 of the closed bore dropouts 102 and 104 by the clampingforce of the quick release lever 7. The slots 32 and 42 in thecompression rings 3 and 4 allow the rings to tighten radially againstthe outer diameter of the mounting axle portion 2 as they simultaneouslytighten against the surfaces of the conical cavities 112 and 114. Ofcourse, materials exist that are transversely compressible and do notrequire such slots, including, but not limited to, the polymer materialsold under the trademark DELRIN. As the compression rings 3 and 4 bindthe axle ends radially to the dropouts, the inboard surfaces of thedropouts 102 and 104 clamp tightly against the ends of the hub 12 in theaxial direction for maximum lateral rigidity of the wheel mounting. Thiswheel clamping assembly is extremely strong and rigid laterally andtorsionally when assembled as described above.

When the longitudinal clamping force against the closed bore dropouts102 and 104 is relieved by pivoting the cam 72 of the quick releaselever 7 away from the thrust washer 9, the return spring 13 urges thecompression ring 3 against the lever 7 so as to prevent excessivelooseness in the lever operation. The assembly 50 can then be removed,in part, from the fork 1 as described below.

In operation the user will install a wheel in the following manner.After inserting the wheel between the fork blades 30 and 40 and aligningthe aperture of the hub with the dropouts 102 and 104, the user slidesthe axle portion 2 through the closed bore dropouts 102 and 104 and thehub 12 and seats the threads 22 of the mounting axle portion 2 againstthe sleeve nut 5. During insertion, the compression ring 3, returnspring 13, pins 8 a and 8 b, linking rod 6, thrust washer 9 and camlever 7 are all mounted to the axle portion 2. Preferably, thecompression ring 4 and sleeve nut 5 remain, at all times after initialinstallation, within the cavity 114 of the dropout 104, as retained bythe wire clip 10.

Because the threads 22 of the axle end are not axially loaded until thequick release lever 7 is pivoted to apply clamping force, the userrotates the sleeve nut 5 by hand relative to the lever end of the axle 2in order to preset the tension of the clamp. If the clamping force iseither too strong or too weak when the lever 7 is pivoted to the closedposition (shown in FIG. 3), the lever 7 can be opened again and both theclamping tension (set by the relative position of the sleeve nut 5 andthe axle portion 2) and the “clocking” (rotational position) of thequick release lever 7 can be conveniently reset by the user before thelever 7 is pivoted closed again. Removal is effected by reversing thesteps—pivoting the lever 7 open, rotating the sleeve nut 5 relative tothe axle portion 2 and withdrawing the axle portion 2 from the hub 12along the length of the axle portion 2.

It will be appreciated that the “wedge effect” created by thelongitudinal force applied against the compression rings 3 and 4securely connects the axle ends to the dropouts 102 and 104 to providesignificant resistance to independent rotational movement of the forklegs 30 and 40 around the wheel axis. The dropouts 102 and 104 aresimultaneously clamped tightly against the hub 12 for lateral rigidityof the wheel mounting. This structure has substantial utility andadvantages as compared to the prior art.

FIG. 4 shows an alternative embodiment of the invention in which thefirst elongated compression member 232 has a conical profile 232 a atone end. This conical profile 232 a mates with the conical taperedcavity 112 of the closed bore dropout 102. The axle portion 202 hasexternal threads 202 a at its distal end, and upon installation thethreads 202 a engage with the internal threads of the knurled nut 205.When the cam lever 207 at the proximal end of the axle assembly 250 isrotated on the axis of the pin 208 after installation of the threads 202a in the knurled nut 205, the nut 205 and abutment member 203 are drawninboard toward one another. This thereby drives the compression members232 and 4 into the tapered cavities of the dropouts 102 and 104,respectively. The inwardly-directed force causes the radially inwardlyfacing surface of the compression member 4 to seat against and clamparound the distal end of the compression member 232 while the radiallyoutwardly facing surface of the compression member 4 seats against andfrictionally engages the tapered cavity 114 (not shown in FIG. 4) of thedropout 104. Simultaneously, axial compression drives the conicalportion 232 a of the compression member 232 into frictional engagementwith the tapered cavity 112 and the inboard faces of the dropouts 102and 104 clamp tightly against the load bearing faces of the hub 12. Theaxle assembly 250 thereby generates resistance to rotational movement ofthe dropouts 102 and 104 relative to each other and simultaneouslyclamps the hub 12 axially to resist lateral movement.

FIG. 5 shows another alternative embodiment of the invention in whichthe compression member 332 has at its proximal end a non-round, taperedprofile 332 a, rather than a conical profile. The non-round profile 332a mates with a corresponding non-round profile extending partially intothe cavity 312 of the closed bore dropout 302. As in the embodiment ofFIG. 4, the conical compression member 4 engages the tapered conicalcavity (not shown in FIG. 5) of the dropout 314. The axle portion 202and cam lever 207 are the same as shown in the embodiment of FIG. 4.Upon installation of the axle portion 202 in the compression member 332with the threads 202 a threaded into the knurled nut 205, rotation ofthe cam lever 207 around the pin 208 draws the compression member 4 intothe tapered cavity of the dropout 314 as the non-round profile 332 a ofthe compression member 332 slidingly engages the mating profile ofcavity 312. Since the non-round profile of the cavity 312 extends onlypartially into the cavity 312, axial movement of the compression member332 is arrested at its proximal end when the non-round profile 332 areaches the limits of the cavity 312. Thereafter, further drawingtogether of the components causes the compression member 4 to wedgefurther against both the cavity of the dropout 314 and the distal end ofthe compression member 332 in frictional engagement as with thecompression member 4 of the FIG. 4 embodiment. The radial clamping inthe dropout 314, the rotational resistance of the non-round matingprofiles in the dropout 312, and the axial clamping of the inboarddropout faces against the load bearing faces of the hub 12 combine toprovide significant resistance to undesirable rotational and lateralmovement of the hub and fork legs relative to each other.

The non-round profile 332 a and the corresponding profiles on thesidewall of the cavity 112 have a “square” shape with sidewalls thattaper toward one another at the inboard end. Of course, a non-roundprofile could be substituted that has a shape with more or fewer thanfour sides, and the sides can be symmetrical and equal or asymmetricaland unequal. For example, a five, six, seven or eight-sided, non-roundprofile could replace that shown in FIG. 5, as could an irregularprofile. Many other examples of profiles that are not round will becomeapparent to a person having ordinary skill from the illustrations anddescription herein.

This detailed description in connection with the drawings is intendedprincipally as a description of the presently preferred embodiments ofthe invention, and is not intended to represent the only form in whichthe present invention may be constructed or utilized. The descriptionsets forth the designs, functions, means, and methods of implementingthe invention in connection with the illustrated embodiments. It is tobe understood, however, that the same or equivalent functions andfeatures may be accomplished by different embodiments that are alsointended to be encompassed within the spirit and scope of the inventionand that various modifications may be adopted without departing from theinvention or scope of the following claims.

The invention claimed is:
 1. A fork for a vehicle, comprising: a firstsubstantially closed-bore dropout defining a first cavity; a secondsubstantially closed-bore dropout defining a second cavity; an axleassembly having a first end and a second end, wherein the second end isthreaded, and wherein the second end of the axle assembly is configuredto pass through the first cavity and enter the second cavity; arotatable fastener having an internal thread capable of mating with thethreaded second end of the axle assembly; and a retainer within thesecond cavity and capable, without mating the fastener with the axle, ofaxially retaining the rotatable fastener, allowing the rotatablefastener to rotate, and restricting axial movement of the rotatablefastener in only a first axial direction; wherein the first cavity, thesecond cavity, and the inner thread of the rotatable fastener aresubstantially aligned along a common axis.
 2. The fork for a vehicleaccording to claim 1, wherein axial movement of the rotatable fastenerin a second axial direction opposite the first axial direction isrestricted by engagement of the rotatable fastener with the seconddropout.
 3. The fork for a vehicle according to claim 2, whereinmovement in the second axial direction is restricted by indirectengagement of the rotatable fastener with the second dropout.
 4. Thefork for a vehicle according to claim 3, wherein the indirect engagementis created by engagement of the rotatable fastener with a compressionmember intermediate the rotatable fastener and the second dropout. 5.The fork for a vehicle according to claim 1, wherein the retainercomprises a wire clip.
 6. The fork for a vehicle according to claim 1,wherein the second cavity has a sidewall and defines a groove in thesidewall.
 7. The fork for a vehicle according to claim 6, wherein theretainer and the groove are configured to interfit with one another. 8.The fork for a vehicle according to claim 1, wherein the rotatablefastener has a flanged end.
 9. The fork for a vehicle according to claim8, wherein the retainer and the flanged end of the rotatable fastenerare capable of interfitting with one another to restrict the axialmovement of the rotatable fastener in the first axial direction.
 10. Thefork for a vehicle according to claim 1, wherein the rotatable fasteneris mounted adjacent the second cavity.
 11. The fork for a vehicleaccording to claim 1, wherein the rotatable fastener is mounted in thesecond cavity.
 12. A suspension system for a bicycle, comprising: afront fork comprising at least a first leg having a lower end, wherein afirst cavity is defined through the first leg; a rotatable fastenerrotatably positioned at least partially within the first cavity; aretainer positioned within the first cavity adjacent the rotatablefastener and, in operable position, substantially preventing axialmotion of the rotatable fastener out of the first cavity in only a firstaxial direction while allowing substantially free rotation of therotatable fastener relative to the first cavity.
 13. The suspensionsystem according to claim 12, wherein the rotatable fastener has athreaded inner surface.
 14. The suspension system according to claim 13,wherein the threaded inner surface is configured to be capable of matingwith a corresponding threaded surface on a first end of an axleassembly.
 15. The suspension system according to claim 12, wherein therotatable fastener further includes an outer flange.
 16. The suspensionsystem according to claim 15, wherein the outer flange is capable ofoperationally engaging the retainer.
 17. The suspension system accordingto claim 12, wherein the first cavity defines a groove.
 18. Thesuspension system according to claim 17, wherein the retainer isconfigured to interfit with the groove.
 19. The suspension systemaccording to claim 12, wherein the retainer is a wire clip.
 20. Thesuspension system according to claim 12, wherein the first cavity isconfigured to restrict axial movement of the rotatable fastener out ofthe first cavity in a second axial direction away from the retainer.